Tempeh is a food obtained by fermentation of soybean grains by the fungus Rizophus oligosporus. It is a traditional Indonesian food that presents benefits for human health protecting against diarrhea and chronic diseases. Tempeh processing includes dehulling, cooking, inoculation, and fermentation. In this study, chemical characteristics of tempeh prepared with soybean cultivars specially developed for human consumption (BRS 216, BRS 232, BRS 257, and BRS 267) were investigated. Soybean grains and tempeh obtained from these cultivars were analyzed for oil, protein, antinutrional factors, and isoflavone content. Cultivar BRS 216 presented the highest protein content in the grains (36.81%) and in tempeh (51.99%). On average, the protein content in tempeh increased 16% in relation to that of soybean grains. Isoflavone content was higher in the grains than in tempeh with significant differences among the cultivars. However, the aglycones content increased about 50% in tempeh (49.00 mg.100 g-1 on average) compared to that of raw material (soybean grains - 21.49 mg.100 g-1, on average). The content of Kunitz trypsin inhibitor (KSTI) reduced 83% in tempeh, on average, as compared to the value found in the grains. Phytic acid content was similar in both tempeh and the grains.
-The objective of this work was to analyze changes in the isoflavone profile, determined by high performance liquid chromatography, at different processing stages and after refrigeration of tempeh. For tempeh production, clean soybean grains from cultivars BR 36 (low isoflavone content) and IAS 5 (high) were dehulled, and the separated cotyledons were hydrated and then cooked in boiling water for 30 min. Spores of the fungus Rhizopus microsporus var. oligosporus were inoculated in the cooked and cooled cotyledons, and incubated at 32ºC for 6, 12, 18, and 24 hours in perforated polypropylene bags, for fermentation. The resulting tempeh was stored at 4ºC for 6, 12, 18, and 24 hours. After 24-hour fermentation, isoflavone glucosides were 50% reduced, and the aglycone forms in the tempeh from both cultivars was increased. The malonyl forms reduced 83% after cooking. Less than 24 hours of refrigeration did not affect the isoflavone profile of tempeh from either cultivar, which is a good indicator of its quality. The tempeh maintains the high and low isoflavone content of the cultivars, which indicates that cultivar differences in this trait should be considered when processing tempeh.Index terms: Rhizopus microsporus var. oligosporus, aglycone, fermentation, functional food, high performance liquid chromatography, malonyl. Mudanças no perfil de isoflavonas e na composição química de 'tempeh' durante o processamento e a refrigeraçãoResumo -O objetivo deste trabalho foi analisar mudanças no perfil de isoflavonas, determinado por meio de cromatografia líquida de alta eficiência, em diferentes estágios do processamento e após refrigeração de 'tempeh'. Para a produção do 'tempeh', grãos de soja limpos das cultivares BR 36 (baixo teor de isoflavonas) e IAS 5 (alto teor) foram descascados, e os cotilédones foram hidratados e, em seguida, cozidos por 30 min em água fervente. Em seguida, esporos do fungo Rhizopus microsporus var. oligosporus foram inoculados nos cotilédones cozidos e resfriados, e incubados a 32ºC por 6, 12, 18 e 24 horas em sacos perfurados de polipropileno, para fermentação. O 'tempeh' resultante foi refrigerado por 6, 12, 18 e 24 horas. Após 24 horas de fermentação, os teores de glicosídeos de isoflavonas reduziram-se em 50%, e os das formas agliconas aumentaram, em ambas as cultivares. Após o cozimento, as formas malonil reduziram-se em 83%. A refrigeração por menos de 24 horas não afetou o perfil de isoflavonas no 'tempeh' das duas cultivares, o que é um bom indicador de sua qualidade. O 'tempeh' mantém os altos e baixos conteúdos de isoflavonas das cultivares, o que indica que as diferenças entre cultivares, para esta característica, devem ser consideradas durante o processamento de 'tempeh'.Termos para indexação: Rhizopus microsporus var. oligosporus, aglicona, fermentação, alimento funcional, cromatografia líquida de alta eficiência, malonil.
Poly(propylene-co-ethylene) composites with rice husk were prepared in a corotating intermeshing twin-screw extruder using four different coupling agents. While modified maleic anhydrides such as maleated polypropylene (MAPP) and maleated polyethylene (MAPE) are commonly used as compatibilizers to improve interfacial adhesion between lignocellulosic filler and matrix, in this study, polypropylene grafted with acid comonomer (CAPP) and high-density polyethylene grafted with acid comonomer (CAPE) were also used. The morphologies and the thermal and mechanical properties of the composites were characterized using scanning electron microscopy, thermogravimetric analysis, differential scanning analysis, tensile and impact tests. The results indicate that the base resin of the compatibilizer is an important factor in determining the effectiveness of compatibilizers for composites. Composites with PP-based compatibilizers are more effective than PE-based compatibilizers due to the improved wetting of the former compatibilizer in the matrix polymer.
The green banana biomass is a new product which has easy applicability in recipes, adding benefits to people's health because it is an ingredient high in resistant starch, recommended for prevention and support in the treatment of diseases such as diabetes, obesity, dyslipidemia, cancer, intestinal disorders, celiac disease etc. The aim of this study was to investigate the potential use of green banana biomass in the preparation of chocolate cake and salty pie. The biomass replaced part of the wheat flour used in the recipes at a ratio of 30% and 50% for the cake and pie, respectively. The green banana biomass, with and without skin, were analyzed for proximate composition. Tests were conducted ranking preference for the cakes and salty pies. The recipe for chocolate cake containing biomass with the peel was the most preferred (60%), and the traditional recipe was the least preferred (54%). In reference to the salty pies, among the most preferred samples, those containing biomass from the pulp of unripe banana came in first place (44%) and, among the least favorite, the traditional recipe prevailed (54%). In an analysis of purchase intention all the preparations had a good intention of purchase. Using the biomass of green bananas for the purpose of using it´s prebiotic property promotes the intake of a functional agent in food in a simple manner, giving rise to a new product.
The epoxidation of polydienes yields materials with improved properties, which can be tuned by the control of the epoxidation degree. In this work, we retake a known process, the epoxidation of polyisoprene, by a different approach, in which the quantification of parameters influencing the epoxidation, such as temperature, oxidant and catalyst concentration, and reaction time degree is evaluated. We measured the influence of each parameter, allowing anyone who aims a polymer with a certain degree of epoxidation to choose which conditions are best suitable for reaching his goal.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2025 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.